Pitman



Get. 15, 1940. w. R. GILLETLTE Filed Jan. 18, 1939 VE WML/AM R. GILLETTEPatented Oct. 15, 1940 PITMAN -William R. Gillette, Maywood', Il l.,assignor Ato Illinois Iron & Bolt Company, Carpentersville, Ill., acorporation of Illinois'A Application January 18, 1939, Serial No.251,455

3 Claims.

The A'present invention relates in general to pitmans and pitmanconnections such as utilized for mowers, combines, harvesters and otheragricultural implements.`

" As is well known in the art, agricultural imple- 'ments such as mowingmachines, grain harvesters and the like, which'utilize a pitman fordriving a cutter bar, the pitman during operation is subj ected toextremely rigorous and hard'usage. The head or vbearing box end of thepitman, which according to the usual practice is connected to a crank orwrist pin carried by a crank disk flywheel xed to a driving shaft, hasbeen a par- -ticular source of trouble. When the cutter bar is adjustedoutof its normal position, thereby changing the plane of operation ofthe cutter bar relative to the crank pin, or, when the crank pin istilted due to the tongue of the mower being Araised or lowered, thepitman is subjected to abnormal stresses which cause undue wear on theparts and not infrequently these stresses cause failure and breakage ofthe parts.

It has therefore been previously proposed to provide a pitman connectionhaving` a single flat plate connecting the pitman bar and the bearing ordriving member connected with the crank wheel of the machine having therequisite thickness and rigidity to transmit the longitudinal forces forreciprocating the p itman, but at the same time having sumcientflexibility to provide the necessary lateral movement to accommodatemisalignment between the crank pin and the cutter bar. In suchconstructions, it has been found that the single flat plate, While in ameasure eliminating some of the difliculties, ultimately failed adjacentits connection to the bearing member, due probably to its being rigidly'anchored in such a way that an abrupt bending line resulted between theanchored portion of the plate and the adjacent exible portion thereof.

In order to overcome such tendency of the plate to fail along this line,the present'invention contemplates a pitman connection employing lateralflexible supplemental plates disposed on either side of the main platein surfacerengagement therewith and projecting a short distanceoutwardly from the bearing member. 'Ivhese plates are normally inactive,but in the event that the main plate is flexed to one side, thesupplemental plate on that side applies pressure against the plate inits area adjacent the rigidly secured portion thereof, thus acting toconne the .plate flexure adjacent its anchored portion to a curvegradually leading into the'plane of its anchored portion, rather thantoA an abrupt bending line (01.74-579) f y i M as in previous'arrangements. In other words, the main and .supplemental plates actinthe manner of a leaf spring in which the amount of flexing is decreasedadjacent the point of support.

It is thereforeanv object ofthe present invention to provide ina pitmanconstruction improvedl means for flexibly connecting aY pitman bar andbearing box. \1

f A further'object ofthe invention is -to provide an 'improved bearingbox construction for a pitlman wherein 'the' bearing parts whichl areconnected to the flexible plate are yprovided with novel means forinterlocking the parts togetherfin 'a circumferential direction foropposingshearing forces.,v n. v, AA still further' object of theinvention is to providefan eflicient lubricating arrangement inv thebearingbox for a pitman. d

' Other objects land features of the invention will more fullyappear'from-the following ``'detailed description'takeniii connectionwith the accompanying drawing whichillustr'ates a single embodimentthereofyan'd in which:

Figure 1 is a 'sideview of the head end of a pitman. connectionembodying theV principles of l the present invention;A

Figure 2 is a plan view of this end ofthe pitman 'showing-the-bearifngbox in section, when viewed along the line IlII in thedirection ofthearrows showninFigurei; j l' 30 Figure 3 is an enlarged Afragmentary Viewof the bearing box, looking at itsleft end as viewed in li'gureandFigure 'fl isl a" fragmentary sectional view through the same,V takensubstantially onA line IV-IV of `Figure 3.

Asshown ontheldrawing: As illustrative Vof the'invention, the 'pitman isdisvclosedas including a wooden 'pitman bar l0 having ari-end slot `l Ifor thereception'of a flat, metallic,'aridfpreferably steeLextensionI2.k This 'extensioriis secured'to thefbarby'aplurality of bolts I3.whic'hY extend through the end of the bar through suitable Aopeningsinthe extension plate. 'The' heads and-nuts of these bolts may overliesuitable sidev plates'l-Mfif desired.

This endl of the plate -I2j maybe tapered as shown.- -The' plate'is ofsuflicient width vto project above and below the ybarili 'and of'sufficient lengthto extend a short distance beyond the end of the barI0, The free end of thegfi'at extension member I2 is apertured toreceivea novel form of bearingbox which is journalled, as is usual in this art,on a crank vpin carried by thefcrank `disk mounted on the mower driveshaft-.V

This bearing box comprises a tubular housing l5 adapted to internallyreceive a bearing sleeve I6.

Intermediate its ends, the housing I5 is thickened to provide acircumferentially extending ange |'I which projects outwardly from acircumferentially extending outer surface portion |8.

The outermost side of this flange is provided at spaced intervals aroundthe housing With integrally formed bolt abutment pads I9, as clearlyshown in Figure 1. In the present instance four of these pads areprovided so that the securing bolts Will be diametrically disposed andspaced at intervals.

The tubular housing is arranged to be introduced into the aperture atthe free end of the extension, and arrangement is made for the placingof coextensive supplemental plates 20 and 2| on both sides of the end ofextension I2. 'Ihese supplemental plates are likewise apertured forreceiving the tubular housing therethrough.

These supplemental plates are also constructed of light flexible,preferably steel, material, and together with the main plate I2 areclamped to the tubular housing by a clamping ring 22 which is clampinglyassociated with the flange |'I and secured in clamped position byclamping bolts 23 which extend through suitable apertures in the padsI9, the plates I2, 20 and 2l and the ring 22. The heads of these boltspreferably are placed in engagement with the pads I9 and the nuts of thebolts tightened against the clamping ring.

In order to interlock the tubular housing with the clamping ring and theplates, the circumferentially extending surfacev I8 is provided withoutwardly extending ribs 24 and 25 adapted to extend into suitablegrooves or notches 26 of the ring 22. The plates I2, 20'and 2| aresimilarly notched to receive the ribs. Thus the bearing box isinterlocked in a circumferential direction with the plates and thisinterlocking opposes the setting up of shearing forces which mightother- Wise tend to shear the securing bolts 23 during the severeoperating conditions imposed upon the pitman.

It will be noted that the plates 20 and 2| extend outwardly from theouter periphery of the clamping ring 22 and flange I'I over the adjacentportion of the plate I2. Y

By virtue of this arrangement, the plates I2, 20 and 2| in effect form aleaf spring construction adjacent the bearing box. It will be noted thatthe plates 20 and 2| normally are inactive in so far as plate I2 isconcerned duringnormal operation. In the event, however, thatmisalignment should occur between the pitman bar l0 and the bearing box,the main plate I2 will be deflected as shown in dotted lines in Figure2. If the plates 20 and 2| were not present, the main plate would tendto be abruptly bent over the peripheral surface of the ange orthe ring22. Continual bending of this nature would cause a failure of the mainplate at this point. However, by inserting the supplemental plates 20and 2|, the bending of the main plate adjacent the bearing box isresiliently opposed so that the plate in this area is flexed in a smoothcurve rather than abruptly, this curve of exure gradually leading intothe plane of the plates where they are clampingly anchored between theflange |'I and ring 22. It will be evident that such an arrangement willprevent breaking of the main plate adjacent its anchored end.

'Ihe interior of the tubular housing is provided intermediate its endswith a circumferentially extending lubricating chamber 21 which isclosed on its inner side by the bearing sleeve I6. This chambercommunicates with the exterior of the housing through a tubular boss 28which may be fitted with a suitable lubricating connection 29 to enablethe introduction of lubricant into the chamber 2I under pressure.

The sleeve I6 is centrally provided with circumferentially spacedopenings 30 which equally distribute the lubricant around the sleeve ina circumferential direction and at a position intermediate its ends. Theinterior of the sleeve I6 is also provided with a longitudinal groove 3|which acts to distribute the lubricant lengthwise of the bearing. Itwill be noted that with this construction, there are no joints in thehousing through which lubricant might flow from the chamber 21 to theexterior thereof.

From the foregoing description, it will be apparent that the presentinvention provides an improved pitman construction in which the pitmanbar is connected to the bearing box in a flexible manner in such a waythat breakage of the connection is prevented due to a flexing thereofresulting from misalignment of the bar with the bearing box; whichembodies an improved bearing boX construction in which the parts areinterlocked in a circumferential direction, thus opposing shearingforces which might shear the bolts for securing the parts together; andwhich includes an eiicient and effective lubricating arrangement forequally distributing lubricant circumferentially around the bearingsleeve.

It is, of course, to be understood that although I have described indetail a preferred embodiment of my invention, the invention is not tobe thus limited, but only in so far as defined by the scope and spiritof the appended claims.

I claim as my invention:

1. A pitman for mowers or the like comprising a bar having alongitudinally extending slot at one end, a flat flexible end taperedplate having one of its tapered ends connected to said bar within saidslot, coextensive flexible reinforcing plates laterally disposed at theother tapered end of said first flexible plate, said flexible platesbeing respectively provided with aligned notched apertures, a bearinghousing formed to provide a substantially tubular portion and aperipherally extending ange, said tubular portion being arranged toextend through and complementally engage said notched apertures withsaid ange `seating against one of said reinforcing plates, a clampingring cooperating with said flange to clamp said flexible platestherebetween, and means securing said ring and flange together forinterlocking the housing and flexible plates in a directioncircumferentially of said housing.

2. A pitman for mowers or the like comprising a bar having alongitudinally extending slot at o-ne end, a flat flexible end taperedplate having one of its tapered ends connected to said bar Within saidslot, a pair of shorter flexible reinforcing plates respectivelydisposed on each side of said tapered plate in face engagement with itsother tapered end, the laminae of plates having aligned notchedapertures therethrough, a bearing housing having a peripheral ange and atubular portion extending axially therefrom, said tubular portion beingprovided with ribs extending along the length thereof, said ribbedtubular portion being disposed in said notched apertures with said angeseated against one of the rein- 75 forcing plates for interlocking thehousing and laminae of plates in a circumferential direction, a clampingring having interior notches adapted to complementalli7` engage saidribbed tubular portion and to cooperate with said ange for clamping theflexible plates therebetween, and securing means extending through saidring, laminae of plates and flange for securing them together, said ribsand notches cooperating to relieve said securing means of shearingstresses.

3. A pitman for mowers or the like comprising a bar having alongitudinaly extending slot at one end, a flat flexible end taperedplate having one of its tapered ends connected to said bar,

Within said slot, a pair of sho-rter exible reinforcing plates in spacedengagement with and on each side of said tapered plate at its otherYtapered end, the laminae of plates having aligned notched aperturestherethrough, a bearing housing including a pair of clamping parts forsecuring said plates together, one of said parts having a peripheraliiange and a tubular portion extending axially therefrom, said tubularportion being provided with ribs extending along its length and disposedin said notched apertures with the flange seated against one of thereinforcingl plates, said one part also dening an interior ocircumferentially extending lubrication chamber having an exteriorconnection, a bearing sleeve in said one part having circumferentiallyspaced openings communicating With said chamber, the other of said partshaving a central aperture provided With interior notches arranged tocomplementally engage the ribbed tubular portion of said one part, saidclamping parts cooperating to clamp'the flexible plates therebetween,and

securing means extending through said laminae of plates and clampingparts for clamping them together, said ribs and notches .cooperating torfelieve the securing means of shearing stresses.

WILLIAM R. GnLE'rIE.

